1. Field of the Invention
The present invention relates to an air bag system wherein an air bag is inflated when impact or deformation is sensed in the event of a vehicle collision and more particularly, to a modular cover adapted to contain an air bag in the system.
2. Description of the Related Art
A conventional modular cover for use in an air bag is illustrated in FIG. 4 and includes a rigid inner layer 11, and a soft outer layer 12. The modular cover is torn along a tear line 13 when the air bag is inflated. The modular cover is made by a two-color molding process wherein two resins are separately injected into a common mold.
During two-color molding process, such a modular cover, composed of inner and outer layers shown in FIG. 4, is subject to shrinkage (sink mark or depression) when resins are cured.
Specifically, depressions (shrinkage) results from curing of the outer layer 12 as shown in FIG. 5. FIG. 5 is an enlarged view of a portion V of the modular cover shown in FIG. 4. Depression or dimples 20 are formed on the surface 12a of the outer layer 12 adjacent to the tear line 13. This deteriorates the appearance of the modular cover. The arrows 21 show the directions in which the material is shrunk.